Act Security has launched Amphi, a free and open-source suite of tools for managing cloud access policies. The suite covers the full policy lifecycle, including reading, testing, simulating, shrinking, converting policies, and querying reachability across cloud environments. Amphi is built on Cloud Copilot, the AWS IAM tool created by David Kerber, which Act Security recently acquired. The tools are available as a CLI that runs offline, a browser version using client-side code, and full source on GitHub. Act Security emerged from stealth in July 2026 with $60 million in funding from investors including Team8, Bessemer Venture Partners, and Notable Capital. The company was founded by the team behind Medigate, which was acquired by Claroty for $400 million.

Act Security launches action-centric cloud security platform with $60 million in funding. Jul 28, 2026, 07:00 ET Founded by the team behind Medigate, Act targets risk at the infrastructure layer by eliminating the access paths behind every breach. TEL AVIV, Israel, July 28, 2026 /PRNewswire/ - Act Security, an action-centric cloud security company, today emerged from stealth with $60 million in total funding and the launch of its cloud security platform. AI has turned point fixes like patching into a losing strategy, flooding security teams with endless tables of misconfigurations and vulnerabilities. Act eliminates the conditions that make them exploitable, systematically reducing the access surface across cloud infrastructure by enforcing boundaries for humans, workloads, and AI agents. Since its founding in 2025, Act has raised a $20 million seed round led by Team8 and Bessemer Venture Partners with participation from Hetz Ventures and Claltech, and a $40 million Series A led by Notable Capital with participation from Startpoint Capital and SVCI. Organizations have accumulated massive access sprawl across their cloud environments, with the vast majority of granted cloud permissions unneeded and unused, creating additional, and compounding, risk. For years, the risk was manageable, as exploitation of vulnerabilities moved at human speed. With AI now operating on every access path and exploiting it at machine speed, this problem has become urgent. When Frontier AI models like Anthropic's Claude Mythos find and exploit access paths faster than any team can respond, and AI agents now run inside production systems with real autonomy, access becomes the primary attack surface of the AI era. Traditional cloud security traps teams in reactive remediation, a model that breaks under the stress of AI's speed. Act eliminates the conditions that make risk exploitable, systematically reducing the access surface across cloud infrastructure by enforcing deterministic boundaries that limit what humans, workloads, and AI agents can reach. These controls are grounded in how the business actually operates and continuously enforced through cloud-native and traditional controls customers already own.By reasoning across identity, network, and AI access together, Act helps organizations regain control, enforce the principle of least privilege, and safely scale AI adoption. "Based on what we are seeing from our customers, close to 97% of cloud access sits dormant and unused, and now AI agents are inheriting those same old human permissions, running around the clock, at machine speed, with none of the judgment a person would apply," said Jonathan Langer, co-founder and CEO of Act Security. "In parallel, Mythos confirmed what much of the cyber world had started to realize, that we can't patch our way out of everything, no matter how hard we try. Visibility tools surface thousands of findings and leave teams triaging symptoms one by one, while the root cause, the access architecture, goes unaddressed. Instead of chasing findings, we remove the conditions that turn risk into a breach, making the cloud structurally secure before attacks unfold." The platform enables organizations to: * Eliminate access paths that attackers, AI-driven and otherwise, exploit. By removing the exposed pathways attackers move through, the attacker has nowhere to go. * Deploy AI agents safely by enforcing tightly defined access boundaries around every AI workload, so agents reach exactly what they need and nothing more. * Clean existing access sprawl and prevent access erosion over time, ensuring new sprawl is not created. The platform continuously validates and tightens boundaries and extends into the CI/CD pipeline so new access violations never reach production. * Achieve provable, continuous compliance with perimeter and data-boundary enforcement mapping directly to controls required by NIST 800-53, PCI DSS, HIPAA and more. "We backed Act because of the caliber of the founding team who saw the access problem before the rest of the market did," said Liran Grinberg, co-founder and Managing Partner at Team8. "Cloud security has spent a decade telling organizations where their risk is. Act is the first platform that actually removes it, and in an era where AI exploits exposure in minutes rather than months, that's the new baseline. We believe this is one of the largest opportunities in cybersecurity today." About Act Security Act Security is an action-centric cloud security company. Rather than surfacing findings, Act eliminates the conditions that make them exploitable, systematically reducing the access surface across cloud infrastructure by enforcing boundaries for humans, workloads, and AI agents. Grounded in how the business actually operates and enforced through the cloud-native controls customers already own, Act helps organizations eliminate attack paths, safely scale AI adoption, and maintain continuous, audit-ready compliance. Act has raised $60 million from investors, including Team8, Bessemer Venture Partners, and Notable Capital, and was founded by the team behind Medigate, the medical-device security company acquired by Claroty for $400 million. For more information, visit: https://act.security/ Act Security Media Contact Raanan Loew Headline Media [email protected] US: +1 347 897 9276 SOURCE Act Security